Wednesday, 23 November 2016

I am sure that by now everyone is aware of Facebook's attempt to connect the people in rural and remote areas. Back in March they published the State of Connectivity report highlighting that there are still over 4 billion people that are unconnected.

The chart above is very interesting and shows that there are still people who use 2G to access Facebook. Personally, I am not sure if these charts take Wi-Fi into account or not.

In my earlier post in the Small Cells blog, I have made a case for using Small Cells as the best solution for rural & remote coverage. There are a variety of options for power including wind turbines, solar power and even the old fashioned diesel/petrol generators. The main challenge is sometimes the backhaul. To solve this issue Facebook has been working on its drones as a means of providing the backhaul connectivity.

Recently Facebook held its first Telco Infra Project (TIP) Summit in California. The intention was to bring the diverse set of members (over 300 as I write this post) in a room, discuss ideas and ongoing projects.

There were quite a few interesting talks (videos available here). I have embedded the slides and the talk by SK Telecom below but before I that I was to highlight the important point made by AMN.

As can be seen in the picture above, technology is just one of the challenges in providing rural and remote connectivity. There are other challenges that have to be considered too.

Some of you may be unaware that the US operator Verizon has formed 'Verizon 5G Technology Forum' (V5GTF) with the intention of developing the first set of standards that can also influence the direction of 3GPP standardization and also provide an early mover advantage to itself and its partners.

Verizon has posted its second round of work with its partners on a 5G specification. The first round was around the 5G radio specification; this time the work has been on the mechanics of connecting to the network. The operator has been working on the specification with Cisco Systems Inc., Ericsson AB, Intel Corp., LG Electronics Inc., Nokia Corp., Qualcomm Inc. and Samsung Corp. via the 5G Technology Forum (V5GTF) it formed late in 2015.Sanyogita Shamsunder, director of strategy at Verizon, says that the specification is "75% to 80% there" at least for a "fixed wireless use case." Verizon is aiming for a "friendly, pre-commercial launch" of a fixed wireless pilot in 2017, Koeppe notes.

Before we go further, lets see this excellent video by R&S wherein Andreas Roessler explains what Verizon is up to:

Verizon and SKT are both trying to be the 5G leaders and trying to roll out a pre-standard 5G whenever they can. In fact Qualcomm recently released a 28 GHz modem that will be used in separate pre-standard 5G cellular trials by Verizon and Korea Telecom

The Snapdragon X50 delivers 5 Gbits/second downlinks and multiple gigabit uplinks for mobile and fixed-wireless networks. It uses a separate LTE connection as an anchor for control signals while the 28 GHz link delivers the higher data rates over distances of tens to hundreds of meters.

The X50 uses eight 100 MHz channels, a 2x2 MIMO antenna array, adaptive beamforming techniques and 64 QAM to achieve a 90 dB link budget. It works in conjunction with Qualcomm’s SDR05x mmWave transceiver and PMX50 power management chip. So far, Qualcomm is not revealing more details of modem that will sample next year and be in production before June 2018.

Verizon and Korea Telecom will use the chips in separate trials starting late next year, anticipating commercial services in 2018. The new chips mark a departure from prototypes not intended as products that Qualcomm Research announced in June.

Korea Telecom plans a mobile 5G offering at the February 2018 Winter Olympics. Verizon plans to launch in 2018 a less ambitious fixed-wireless service in the U.S. based on a specification it released in July. KT and Verizon are among a quartet of carriers that formed a group in February to share results of early 5G trials.

For its part, the 3GPP standards group is also stepping up the pace of the 5G standards efforts it officially started earlier this year. It endorsed last month a proposal to consider moving the date for finishing Phase I, an initial version of 5G anchored to LTE, from June 2018 to as early as December 2017, according to a recent Qualcomm blog.

Coming back to Verizon's 5G standard, is it good enough and compatible with 3GPP standards? The answer right now seems to be NO.

The issue is that Verizon’s specs include a subcarrier spacing value of 75 kHz, whereas the 3GPP has laid out guidelines that subcarrier spacing must increase by 30 kHz at a time, according to research from Signals Research Group. This means that different networks can work in synergy if required without interfering with each other.Verizon’s 5G specs do stick to 3GPP requirements in that it includes MIMO and millimeter wave (mmWave). MmWave is a technology that both AT&T and Verizon are leading the way in – which could succeed in establishing spectrum which is licensed fairly traditionally as the core of the US’s high frequency build outs.A Verizon-fronted group recently rejected a proposal from AT&T to push the 3GPP into finalizing an initial 5G standard for late 2017, thus returning to the original proposed time of June 2018. Verizon was supported by Samsung, ZTE, Deutsche Telecom, France Telecom, TIM and others, which were concerned the split would defocus SA and New Radio efforts and even delay those standards being finalized.Verizon has been openly criticized in the industry, mostly by AT&T (unsurprisingly), as its hastiness may lead to fragmentation – yet it still looks likely to beat AT&T to be the first operator to deploy 5G, if only for fixed access.Verizon probably wants the industry to believe that it was prepared for eventualities such as this – prior to the study from Signal Research Group, the operator said its pre-standard implementation will be close enough to the standard that it could easily achieve full compatibility with simple alterations. However, Signals Research Group’s president Michael Thelander has been working with the 3GPP since the 5G standard was birthed, and he begs to differ.Thelander told FierceWireless, “I believe what Verizon is doing is not hardware-upgradeable to the real specification. It’s great to be trialing, even if you define your own spec, just to kind of get out there and play around with things. That’s great and wonderful and hats off to them. But when you oversell it and call it 5G and talk about commercial services, it’s not 5G. It’s really its own spec that has nothing to do with Release 16, which is still three years away. Just because you have something that operates in millimeter wave spectrum and uses Massive MIMO and OFDM, that doesn’t make it a 5G solution.”

Back in the 3G days, NTT Docomo was the leader in standards and it didn't have enough patience to wait for 3GPP standards to complete. As a result it released its first 3G network called FOMA (Freedom of Mobile Access) based on pre-standard version of specs. This resulted in handset manufacturers having to tweak their software to cope with this version and it suffered from economy of scale. Early version of 3G phones were also not able to roam on the Docomo network. In a way, Verizon is going down the same path.

While there can be some good learning as a result of this pre-5G standard, it may be a good idea not to get too tied into it. A standard that is not compliant will not achieve the required economy of scale, either with handsets or with dongles and other hotspot devices.

The big issue with VoLTE has always been the complexity. In a post last year I provided a quote from China Mobile group vice-president Mr.Liu Aili, "VoLTE network deployment is the one of the most difficult project ever, the implementation complexity and workload is unparalleled in history".

From a recent information published by IHS, there will only be 310 million subscribers by end of 2016 and 2020 is when 1 billion subscribers can make use of VoLTE. I think the number will probably be much higher as we will have VoLTE by stealth.

Below are couple of case studies, one from SK Telecom, presented by Chloe(Go-Eun) Lee and other from Henry Wong, CTO Mobile Engineering, Hong Kong Telecom (HKT). Hope you find them informative and useful.

Sunday, 1 November 2015

Last year's summary of the LTE voice summit was very much appreciated so I have created one this year too.

The status of VoLTE can be very well summarised as can be seen in the image above.

‘VoLTE network deployment is the one of the most difficult project ever, the implementation complexity and workload is unparalleled in history’ - China Mobile group vice-president Mr.Liu Aili

Surprisingly, not many presentations were shared so I have gone back to the tweets and the pictures I took to compile this report. You may want to download the PDF from slideshare to be able to see the links. Hope you find it useful.

Thursday, 3 October 2013

Recently I came across this whitepaper by iGR, where they have done a case study on the SKT deployment using C-RAN. The main point can be summarised from the whitepaper as follows:

This approach created several advantages for SK Telecom – or for any operator that might implement a similar solution – including the:

Maximum re-use of existing fiber infrastructure to reduce the need for new fiber runs which ultimately reduced the time to market and capital costs.

Ability to quickly add more ONTs to the fiber rings so as to support additional RAN capacity when needed.

Support of multiple small cells on a single fiber strand. This is critical to reducing costs and having the flexibility to scale.

Reduction of operating expenses.

Increased reliability due to the use of fiber rings with redundancy.

Support for both licensed and unlicensed RAN solutions, including WiFi. Thus, the fronthaul architecture could support LTE and WiFi RANs on the same system.

As a result of its implementation, SK Telecom rolled out a new LTE network in 12 months rather than 24 and reduced operating expenses in the first year by approximately five percent. By 2014, SK Telecom expects an additional 50 percent OpEx savings due to the new architecture.

Anyway, the paper is embedded below for your perusal and is available to download from the iGR website here.